The present invention generally relates to methods and apparatuses for converting heat energy into other forms of energy. In addition, the invention relates to methods and other accommodations for dissipating heat away from devices generating heat.
Generally, the Second Law of Thermodynamics states that heat will travel from a hotter medium to a cooler medium. Further, as is known, hot air rises as the heated air expands and seeks to migrate to a lower pressure area, thereby creating what is known as natural convection. This process is commonly referred as the xe2x80x9cchimney effect.xe2x80x9d
Since the thermodynamic xe2x80x9cavailability,xe2x80x9d or energy content, of a solid or fluid increases strongly with absolute temperature, efficient electric power generation from a heat source is usually performed at elevated temperatures, often in the range of 600xc2x0 C.-800xc2x0 C. In the categories of high temperature conversion, these systems are generally large, with each generator unit producing megawatts of electric power and occupying a volume of 10 m3 to 100 m3. Alternatively, lower temperature equipment operating between 100xc2x0 C. and 200xc2x0 C., have been developed to recover energy from solar-concentrator heated fluids and geothermal sources and waste heat rejected by high temperature conversion systems.
In the marketplace, many products generate heat in the low temperature range below 150xc2x0 C. For example, electrical components, such as integrated circuits including a central processor unit (CPU) for a computer and operating in close proximity in an enclosed electronic apparatus, produce heat. To prevent thermal failure of one of the electrical components in the enclosed electronic apparatus this heat needs to be dissipated. These enclosed electronic apparatuses are common and typically include personal computers, laptop computers, display monitors, computer peripherals, television sets, projectors, projection monitors, handheld personal digital assistants (PDAs), cellular phones, facsimile machines, video cassette recorders (VCRs), digital versatile disc (DVD) players, audio systems and similar equipment. Further, slightly larger equipment, such as refrigerators, washers, dryers and other similar appliances also may generate heat in this low temperature range.
Thermal management of the electronic components in the enclosed electronic apparatus is necessary to prevent the enclosed electronic apparatus from failing or to extend the useful life of the enclosed electronic apparatus. For instance, a typical CPU operating in a personal computer may operate at a maximum temperature of 70xc2x0 C. without experiencing a thermal failure; but due to the heat generated by a typical CPU, however, the temperature often reaches 100xc2x0 C. and above which could lead to thermal failure.
The present invention provides systems, methods and apparatus for applying the xe2x80x9cchimney effectxe2x80x9d to enhance natural convection cooling of an electrical component.
The present invention provides systems, methods and apparatus for dissipating heat emitted by an electrical component and for dissipating the heat out of an electrical device.
The present invention provides systems, methods and apparatus for converting relatively low temperature waste heat into other useful forms of energy. The invention is especially useful for generating electrical energy from relatively low temperature heat.
In an embodiment, the present invention provides that relatively lower temperature heat energy is transferred to a fluid medium in a channel and that natural convection of the fluid medium is utilized to generate another useful energy, preferably electricity. As used herein, a xe2x80x9cfluid mediumxe2x80x9d unless otherwise noted is included to mean any flowable medium such as gas or liquid.
In an embodiment, the present invention provides an improved heat dissipater and method for using same in which dissipated heat is converted to work energy. Heat generated by electrical components is dissipated via a channel internally housed within an enclosure.
In an embodiment, the channel can have an inlet and an outlet and a nozzle section for generating an increased flow portion within the channel.
In an embodiment, a plurality of such channels are provided with each channel sized and shaped for paralleably extending across the electrical device.
In an embodiment, the present invention provides a plurality of heat transfer members which are adjacently disposed to a plurality of electrical components where each electrical component generates heat. Each heat transfer member thermally connects each electrical component to the channel wall for maintaining a temperature differential between the electrical component and the channel. This temperature differential generates fluid medium flow by natural convection through the channel to the outlet and out of an enclosure.
In an embodiment, to direct the heated air flow from a plurality of such channels, a manifold is provided which thermally connects to each outlet for combining the heated flow of fluid medium of each outlet and directing the heated air flow out of the enclosure.
Further, in an embodiment, the invention provides an energy converter that harnesses the heated fluid medium flow. The energy converter may have a turbine mounted at the outlet of the channel. Alternatively, the turbine can be mounted in any other appropriate portion of the channel, one example of which is a nozzle section of the channel mentioned above. The energy converter is connected to an electrical storage for transferring power generated by the turbine to an external load.
In an embodiment, for increased air flow out of the enclosure, the invention provides for an extendable channel that is removably fixed to the channel. This extendable channel can be caused to extend either manually or by a suitable automatic mechanism.
The present invention also provides for methods of using such heat dissipating devices. In that regard, the method in accordance with one aspect of the invention comprises the steps of conducting heat away from an electronic component into a channel and transferring the conducted heat to a fluid medium disposed within the channel.
Next, the method provides creating a natural convection fluid flow effect in the fluid medium by virtue of the transfer of heat. Further, the energy is harnessed by the fluid medium flow to generate another form of energy. In one method, the form of energy is electrical energy.
In one method, the step of harnessing the energy provided by the fluid flow comprises the step of using the fluid medium flow to drive a turbine connected to an energy converter.
The present invention has many advantages. These advantages relate to an enhanced cooling of an electrical component and generating power from the heat given off by the electrical component.
An advantage of the invention is the ability to transfer the heat given off from the electrical component to a fluid medium, which in turn is subject to flow due to natural convection caused by transfer of heat to the fluid medium.
Another advantage of the invention is the ability to derive electricity from the natural convection and to supply the electricity to an electrical storage without requiring additional energy.
These and other advantages and aspects of the present invention are set forth in greater detail in the following detailed description of the presently preferred embodiments with reference to the attached drawings.